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Fork innards exposed


pattonme

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The pictures are of an FZ09.
 
Yes, the valving is light. The pistons aren't great but I've seen much worse from Kayaba in the past. But to do as they did under the rubric of a cost-savings measure, it's an epic FAIL.
 
They saved (in retail prices, mind you) $15 in shims, $20 in pistons, 10 cents in removing the adjuster rod, and probably another $10 in other bits to give FZ owners a most lousy riding experience. But worse, they retained the complicated and expensive to machine fork cap body with all it's fiddly bits, and all of the expensive cartridge tube parts (it's polished inside) when a plain ol' tube would have cost pennies. Then they drilled an extra set of holes in said tube only so that it would not trap (as much) air on fill-up. But had they just not included the rebound rod there would have been a 10mm hole left for that purpose. Even better, they created a damper rod that is like it's sibling but 20mm longer and machined to not have threads on it's extra length. On the end where the piston would go they attached a dummy cap. So now you have this rod that is attached to nothing useful sliding up and down inside a chamber just stirring up some oil. It's sole purpose in life is to hold the fluid lock.
 
Whereas the big, aluminum body used as a glorified spring seat has no Lock-tite on it, the cartridge base which has the same threads has to be heated to crazy hot to release it.
 
They could have saved another easy $150 (3-500 in MSRP) in direct costs and kept the SKU count down to boot. Somebody over there is none too bright.
 
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The pictures are of an FZ09. 
Yes, the valving is light. The pistons aren't great but I've seen much worse from Kayaba in the past. But to do as they did under the rubric of a cost-savings measure, it's an epic FAIL.
 
They saved (in retail prices, mind you) $15 in shims, $20 in pistons, 10 cents in removing the adjuster rod, and probably another $10 in other bits to give FZ owners a most lousy riding experience. But worse, they retained the complicated and expensive to machine fork cap body with all it's fiddly bits, and all of the expensive cartridge tube parts (it's polished inside) when a plain ol' tube would have cost pennies. Then they drilled an extra set of holes in said tube only so that it would not trap (as much) air on fill-up. But had they just not included the rebound rod there would have been a 10mm hole left for that purpose. Even better, they created a damper rod that is like it's sibling but 20mm longer and machined to not have threads on it's extra length. On the end where the piston would go they attached a dummy cap. So now you have this rod that is attached to nothing useful sliding up and down inside a chamber just stirring up some oil. It's sole purpose in life is to hold the fluid lock.
 
Whereas the big, aluminum body used as a glorified spring seat has no Lock-tite on it, the cartridge base which has the same threads has to be heated to crazy hot to release it.
 
They could have saved another easy $150 (3-500 in MSRP) in direct costs and kept the SKU count down to boot. Somebody over there is none too bright.

Thanks for the detailed description. When it comes to suspension and the internal workings I do not have the technical knowledge, so i appreciate you talking through. From what you have said it is a disappointment in spending more wisely Yamaha could have produced a truly epic bike and great riding experience and an awesome price point. 
 
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They chose to use 0.125 shims which is odd. Maybe they thought they'd try something new. On the face of it the valving isn't horrible, but with only one leg doing the damping, you can't just use the setup that works when there are 2 legs handling the load. The right answer isn't necessarily '2x' but it's definitely not to go same or +15% more than an equivalent bike that uses 4 pistons. I would bet they developed the stack with both legs doing the damping and at the last minute some damn accountant said "no, we can save $50 bucks, so lose the other leg" and the engineers forgot to revise the setup. Getting crucified in the press forced them to ship a beefed up stack for the FJ that was ~2x what the FZ had originally.
 
 
Compression:
16 x 0.125 - 5
15 x 0.125
14 x 0.125
13 x 0.125
12 x 0.15
11 x 0.15
 
Rebound:
16 x 0.15 - 3
15 x 0.125 - 2
14 x 0.125 - 2
12 x 0.125 - 2
 
 
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